--- /dev/null
+/* ----------------------------------------------------------------------
+* Copyright (C) 2010-2013 ARM Limited. All rights reserved.
+*
+* $Date: 17. January 2013
+* $Revision: V1.4.1
+*
+* Project: CMSIS DSP Library
+* Title: arm_scale_f32.c
+*
+* Description: Multiplies a floating-point vector by a scalar.
+*
+* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions
+* are met:
+* - Redistributions of source code must retain the above copyright
+* notice, this list of conditions and the following disclaimer.
+* - Redistributions in binary form must reproduce the above copyright
+* notice, this list of conditions and the following disclaimer in
+* the documentation and/or other materials provided with the
+* distribution.
+* - Neither the name of ARM LIMITED nor the names of its contributors
+* may be used to endorse or promote products derived from this
+* software without specific prior written permission.
+*
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+* POSSIBILITY OF SUCH DAMAGE.
+* ---------------------------------------------------------------------------- */
+
+#include "arm_math.h"
+
+/**
+ * @ingroup groupMath
+ */
+
+/**
+ * @defgroup scale Vector Scale
+ *
+ * Multiply a vector by a scalar value. For floating-point data, the algorithm used is:
+ *
+ * <pre>
+ * pDst[n] = pSrc[n] * scale, 0 <= n < blockSize.
+ * </pre>
+ *
+ * In the fixed-point Q7, Q15, and Q31 functions, <code>scale</code> is represented by
+ * a fractional multiplication <code>scaleFract</code> and an arithmetic shift <code>shift</code>.
+ * The shift allows the gain of the scaling operation to exceed 1.0.
+ * The algorithm used with fixed-point data is:
+ *
+ * <pre>
+ * pDst[n] = (pSrc[n] * scaleFract) << shift, 0 <= n < blockSize.
+ * </pre>
+ *
+ * The overall scale factor applied to the fixed-point data is
+ * <pre>
+ * scale = scaleFract * 2^shift.
+ * </pre>
+ *
+ * The functions support in-place computation allowing the source and destination
+ * pointers to reference the same memory buffer.
+ */
+
+/**
+ * @addtogroup scale
+ * @{
+ */
+
+/**
+ * @brief Multiplies a floating-point vector by a scalar.
+ * @param[in] *pSrc points to the input vector
+ * @param[in] scale scale factor to be applied
+ * @param[out] *pDst points to the output vector
+ * @param[in] blockSize number of samples in the vector
+ * @return none.
+ */
+
+
+void arm_scale_f32(
+ float32_t * pSrc,
+ float32_t scale,
+ float32_t * pDst,
+ uint32_t blockSize)
+{
+ uint32_t blkCnt; /* loop counter */
+#ifndef ARM_MATH_CM0_FAMILY
+
+/* Run the below code for Cortex-M4 and Cortex-M3 */
+ float32_t in1, in2, in3, in4; /* temporary variabels */
+
+ /*loop Unrolling */
+ blkCnt = blockSize >> 2u;
+
+ /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
+ ** a second loop below computes the remaining 1 to 3 samples. */
+ while(blkCnt > 0u)
+ {
+ /* C = A * scale */
+ /* Scale the input and then store the results in the destination buffer. */
+ /* read input samples from source */
+ in1 = *pSrc;
+ in2 = *(pSrc + 1);
+
+ /* multiply with scaling factor */
+ in1 = in1 * scale;
+
+ /* read input sample from source */
+ in3 = *(pSrc + 2);
+
+ /* multiply with scaling factor */
+ in2 = in2 * scale;
+
+ /* read input sample from source */
+ in4 = *(pSrc + 3);
+
+ /* multiply with scaling factor */
+ in3 = in3 * scale;
+ in4 = in4 * scale;
+ /* store the result to destination */
+ *pDst = in1;
+ *(pDst + 1) = in2;
+ *(pDst + 2) = in3;
+ *(pDst + 3) = in4;
+
+ /* update pointers to process next samples */
+ pSrc += 4u;
+ pDst += 4u;
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+
+ /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
+ ** No loop unrolling is used. */
+ blkCnt = blockSize % 0x4u;
+
+#else
+
+ /* Run the below code for Cortex-M0 */
+
+ /* Initialize blkCnt with number of samples */
+ blkCnt = blockSize;
+
+#endif /* #ifndef ARM_MATH_CM0_FAMILY */
+
+ while(blkCnt > 0u)
+ {
+ /* C = A * scale */
+ /* Scale the input and then store the result in the destination buffer. */
+ *pDst++ = (*pSrc++) * scale;
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+}
+
+/**
+ * @} end of scale group
+ */
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